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1 – 10 of over 2000Alan Richardson, Kathryn A. Coventry, Alan M. Forster and Chris Jamison
Deterioration in natural stone is associated with many decay mechanisms and often the inherent composition of the materials themselves. Sandstone varies considerably but they all…
Abstract
Purpose
Deterioration in natural stone is associated with many decay mechanisms and often the inherent composition of the materials themselves. Sandstone varies considerably but they all require a cementing matrix to bind amongst others, the silica (SiO2) particles together (Reading, 1989). In calcareous sandstones and limestones this binding matrix is principally calcium carbonate based (Muir, 2006; Reading, 1989; McMillan et al., 1999) in the form of calcite (CaCO3). Friable sandstone substrates and stones suffering from “surface dissolution” or disaggregation (Muir, 2006; Smith et al., 1992) have been traditionally consolidated utilising a host of chemical compounds that had, in many cases negative effects on their long-term performance (Muir, 2006). A principle issue amongst many was moisture entrapment and irreversibility of the consolidants adopted. The paper aims to discuss these issues.
Design/methodology/approach
This paper investigates the effect of microbial induced calcite precipitation (MICP) as a natural treatment for the conservation of historic natural stone substrates. Sporosarcina pasteurii has been proven as a bacterium that can perform MICP effectively in extreme conditions making it the preferred bacterium for the MICP process within this study. Surface treatment experiments were analysed by measuring the mass increase and surface changes using scanning electron microscopy (SEM).
Findings
The surface treatments showed a noticeable mass increase and observable deposition when viewed using a SEM microscope. Bio cementation of loose sand particles was observed and the degree of cementation was determined using a Moh's hardness test.
Research limitations/implications
Recommendations for further work to improve this study are: use an increased Sporosarcina pasteurii cell optical density which would provide a greater calcite output. Carry out a paired comparison initial surface absorption test (BS 1881: Part 208, 1996 or ASTM C 1585-04, 2004). To be carried out on untreated control and MICP samples which would determine the pore blocking effect and surface repair capability of the treated samples.
Practical implications
A method for obtaining optimal results in terms of surface treatment would involve reducing the time between mixing and application, this would require having the two reaction constituents mixed only seconds before use. Using a late mix spray application system has the potential to allow the two mixtures to combine in the spray nozzle whilst exiting the apparatus.
Originality/value
This paper investigates a safe, natural process for stone repair.
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Calcium stearate has been incorporated into carbon paper (7683), e.g. as a filler (7684), and in paper coatings (7685). It can act as a lubricant, leveller, and plasticizer in…
Abstract
Calcium stearate has been incorporated into carbon paper (7683), e.g. as a filler (7684), and in paper coatings (7685). It can act as a lubricant, leveller, and plasticizer in paper coatings (7686), and gives improved anti‐dust and gloss properties in calendering (7687), and enhanced flow and levelling (7688). Along with ammonium stearate the calcium soap has been used as a lubricant in paper coatings to improve tear strength and gloss (7689), and wet strength. Paper and paperboard have been coated with equal parts of calcium stearate and acrylic/styrene copolymers to increase water resistance (7690). Particles of aluminium hydroxide have been coated with calcium stearate and with stearic acid to give the material hydrophobic properties, resistant to exposure to boiling water and solvents, and useable as a filler in paper (and plastics) (7691). Ketene dimers along with calcium stearate have been used in paper sizing (7692), and the stearate alone has been used to make water resistant abrasive papers (7693), and also, at a concentration of 2/3%, has been employed to render cardboard resistant to water steeping and swelling (7694). Stable dispersions of the stearate soap have been utilized in the surface treatment of computer cards (7695). Titanium dioxide coated with calcium stearate has been included in polyethylene coating compositions for photographic paper supports (7696). Release paper for adhesive lables have contained calcium stearate, to give improved workability on automatic labelling machines (7697).
Life is made up of debits and credits, as Kipling wrote, long accounts have to be paid — mistakes, misconduct, misdeeds, all the mischief and harm they cause, exact payment which…
Abstract
Life is made up of debits and credits, as Kipling wrote, long accounts have to be paid — mistakes, misconduct, misdeeds, all the mischief and harm they cause, exact payment which has to be met by someone, not necessarily those that cause the trouble; all too often by innocent victims. The recent industrial strife, destruction and violence, despite the plausible excuses for it, will have disastrous results, a colossal debit in the nation's accounts; and the mass of the people, the vulnerable groups including several millions of elderly pensioners, the handicapped and sick, are under no illusions who will have to pay. The posturing defiance — “heads held high”, bands playing martial music — the complete lack of concern or regret for others will make no difference to the overtaking retribution.
Theofani Tzevelekou, Spyros Papaefthymiou, Vasiliki Panteleakou, Athanasios Vazdirvanidis, Dimitris C. Papamantellos and Panagiotis Sismanis
A failed disc that was forged from S355J2 round bar was investigated in order to determine the failure route cause. The purpose of this paper is to determine the defects and route…
Abstract
Purpose
A failed disc that was forged from S355J2 round bar was investigated in order to determine the failure route cause. The purpose of this paper is to determine the defects and route cause analysis regarding their origin.
Design/methodology/approach
Macroscopic evaluation, microstructure observation using light optical metallography and scanning electron microscopy with EDX analysis were the techniques used to analyse and characterize the defected areas.
Findings
Macro-inclusions (up to 850 µm) that correspond to high melting aluminium rich calcium-aluminate particles were detected. Their formation, possibly due to improper calcium treatment during ladle furnace steel refining process might be associated with clogging problems at casting. SEM-EDX analysis revealed whitish spots containing Zr that could be related to submerged entry nozzle (SEN) erosion/breakage. Characteristic is the large size and unusual shape of the traced particles, as well as the presence of low Si, Na, K. The findings indicated that nozzle clogging and/or breakage at casting was most possibly the root cause of the product’s quality degradation.
Originality/value
After extended root cause analysis, specific countermeasures are proposed to avoid clogging phenomena. The suggestions are based on the findings taking into account restrains of the steel-making process. Emphasis was laid in detecting the weaknesses that lead to product quality degradation and consequently in optimizing the steel-making process. Such incidents are often found during steelmaking a useful suggestion to steelmakers is to mark and remove cast parts after SEN problems are encountered. In this way quality issues in intermediate and/or final products will be avoided.
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Sandriane Pizato, Raquel Costa Chevalier, Marcela Félix Dos Santos, Tailine Saturnino Da Costa, Rosalinda Arévalo Pinedo and William Renzo Cortez Vega
The purpose of this paper is to evaluate the shelf-life of minimally processed pineapple when subjected to the use of different edible coatings.
Abstract
Purpose
The purpose of this paper is to evaluate the shelf-life of minimally processed pineapple when subjected to the use of different edible coatings.
Design/methodology/approach
The pineapples were peeled and cut into cubes. The gums were prepared by dissolving them in distilled water and then heated to total dissolution. After calcium chloride, citric acid and ascorbic acid and glycerol were added in the solutions. The pieces of pineapple were completely submerged in the respective solutions and then drained. Four treatments were obtained, namely: T1 – control treatment (pineapple without coating); T2 – pectin; T3 – tara; T4 – xanthan. The cubes were stored in PET by 12 days at 4±1°C. Analyzes were carried out of mass loss, pH, titratable acidity, soluble solids, microbiological and sensory analysis.
Findings
It was possible to observe that the use of evaluated coatings was efficient to maintain the conservation of minimally processed pineapple in all analyzes, when compared with the control sample. The treatment with tara gum showed the best results to those obtained by the other studied gums.
Practical implications
The study may help small-scale establishments to increase the shelf-life of minimally processed pineapple.
Originality/value
Tara gum reduced the mass loss, delayed the microbial growth and maintained the sensorial quality of minimally processed pineapples for a longer time.
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Due to the increased consumption of fast foods in India, especially among the youngsters, obesity and related health ailments have become a serious concern. Fast foods provide…
Abstract
Purpose
Due to the increased consumption of fast foods in India, especially among the youngsters, obesity and related health ailments have become a serious concern. Fast foods provide empty calories which calls for an urgent need to improvise their nutritional value rendering them “nutrient dense”. The purpose of this research was development and nutritional evaluation of baked products incorporated with partially defatted peanut flour.
Design/methodology/approach
Three baked products, namely, pizza base, buns and bread were developed using standardized recipes with different levels of incorporation of defatted peanut meal flour. These products were organoleptically evaluated by a trained panel of ten judges using nine-point hedonic scale. The selected samples of each product were nutritionally evaluated for proximate composition and mineral content along with their respective control samples.
Findings
Results from sensory evaluation revealed that pizza base, buns and bread were most acceptable at 10, 10 and 15 per cent level of incorporation of partially defatted peanut flour, respectively. The developed products were found to have high protein, crude fiber, calcium and iron, i.e. 11.5-12.4 per cent, 1.4-1.8 per cent, 19.2-20.4 mg/100 g, 1.8-2.3 mg/100 g content, respectively. p-values for the same were also calculated.
Originality/value
Keeping in view the nutritional benefits of peanut flour and trending consumption of bakery products among children and other age groups, these products can be commercialized to improve the nutritional value of empty calorie baked products as these products are consumed very frequently. Defatted peanut meal although being nutrient rich has generally been used as animal feed or is discarded as waste. The role of this meal in the human diet has not been explored to the best.
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Earlier in the year, during the national steel industry strike, the House of Lords overturned a judgment of Lord Denning, MR, that sections of the industry unaffected by the trade…
Abstract
Earlier in the year, during the national steel industry strike, the House of Lords overturned a judgment of Lord Denning, MR, that sections of the industry unaffected by the trade dispute could be regarded as outside the Act and its amendments and that unions could be restrained in their application of immune activities to those firms. The decision apart, their Lordships in delivering judgment reaffirmed that only Parliament had power to make the Law; it was not the function of Judges to do this, their's to interpret and apply the Law. In strict legal terms and applying to statutes and statutory instruments, this is true; but in the widest sense, judges have been making law for centuries. Otherwise, from whence cometh the Common Law, one of the wonders of the world, if not from the mouths of H.M. Judges. Much of it is now enshrined in statute form, especially Criminal Law, but initially it was all judge‐made. In most systems of human control and function, complete separation is rarely possible and when attempted the results have not been conspicuously successful.
Steam contamination (solid particles in the superheated steam) comes from the boiler water largely in the carry‐over of water droplets. The need for extreme purity of steam for…
Abstract
Steam contamination (solid particles in the superheated steam) comes from the boiler water largely in the carry‐over of water droplets. The need for extreme purity of steam for use in high pressure turbines has prompted the development of highly satisfactory devices for separating steam and water in a boiler drum. Consequently, steam contamination has been steadily reduced. Troublesome turbine blade deposits may occur with surprisingly low (0.6 ppm) total solids contamination in steam. In the 3.5–6 MPa range, however these deposits are usually water soluble and can be removed by periodic washing. In the 4 to 10 MPa range, however, silica deposits predominate and these deposits are not easily removed by water washing. With operating pressure of 13 MPa and above insoluble deposits do occur which may be controlled by residual water washing. Before the unit is returned to service, the deposits should be removed by air or water‐driven turbine cleaners or by chemical cleaning.
Eduardo Alencar de Souza and José Antônio da Cunha Ponciano Gomes
– The aim was to study the effect of an electromagnetic treatment used on corrosion control of carbon steel in cooling systems.
Abstract
Purpose
The aim was to study the effect of an electromagnetic treatment used on corrosion control of carbon steel in cooling systems.
Design/methodology/approach
The aim was to assess the performance of an electromagnetic treatment used on corrosion control of carbon steel in cooling water systems.
Findings
The main conclusion is that the electromagnetic system cannot induce a direct effect on the corrosion rates. The use of chemical corrosion inhibitors cannot be suggested.
Social implications
The optimized industrial use of water is an objective of unquestionable importance, as water is a finite resource. The use of efficient corrosion control on water cooling systems permits the reduction of the water volume required. Consequently, a social benefit can be associated with the improvement of corrosion control technologies.
Originality/value
The development of alternative corrosion control technologies, such as the use of physical treatments, has been considered as a promising tool. In this work, a consistent assessment of the results achieved on a full-scale system, without using chemical corrosion inhibitors, is presented.
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The terms are not synonymous; their differences are mainly of function and areas of administration. Community Health is used in national health service law; environmental health…
Abstract
The terms are not synonymous; their differences are mainly of function and areas of administration. Community Health is used in national health service law; environmental health to describe the residuum of health functions remaining with local authorities after the first NHS/Local Government reorganization of 1974. Previously, they were all embraced in the term public health, known for a century or more, with little attention to divisions and in the field of administration, all local authority between county and district councils. In the dichotomy created by the reorganization, the personal health services, including the ambulance service, may have dove‐tailed into the national health service, but for the remaining functions, there was a situation of unreality, which has persisted. It is difficult to know where community health and environmental health begin and end. From the outside, the unreality may be more apparent than real. The Royal Commission on the NHS in their Report of last year state that leaving environmental health services with local authorities “does not seem to have caused any problems”—and this, despite the disparity in status of the area health authority and the bottom tier, local councils.